The invention is directed to moldable and vulcanizable mixtures which contain as essential constituents a halogen rubber, a silicate filler, in a given case admixed with carbon black and a cross-linking system for the halogen rubber.
It is known that sulfur vulcanizable rubber mixtures which have a high content of silicate fillers, as for example precipitated silica, absolutely require as a component of the mixture a silane in order to obtain sufficiently good properties in the vulcanization. Such silanes for example are the outstandingly suited but of a relatively high expense to produce bis-(alkoxysilylalkyl)-oligosulfides as for example bis(triethoxysilylpropyl)-tetrasulfide. An alternative to the separate addition of silicate fillers and silanes to the rubber mixtures consists in previous mixtures of the mentioned materials (Thurn U.S. Pat. No. 3,873,489). The entire disclosure of Thurn is hereby incorporated by reference and relied upon.
It is also known to prepare a crosslinkable rubber mixture which includes a sulfur containing organosilane, a known vulcanization accelerator and as filler a silicate filler, but which does not contain elemental sulfur, see Belgian Pat. No. 832,970 and Wolff U.S. application Ser. No. 835,848, filed Sept. 22, 1977.
There are also known mixtures based on SBR and EPDM rubbers containing a mercaptosilane such as 3-mercaptopropyltrimethoxysilane, a vinyl silane such as vinyl trimethoxysilane and an amino silane such as 3-aminopropyltriethoxysilane, Rubber World, October 1970, pages 54 and 55.